<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<link src="${pageContext.request.contextPath}/static/jquery.min.js">
<script type="text/javascript">
	function a() {
		$.post({
			url:"${pageContext.request.contextPath}/test2",
			data:{"name":$("#username").val()},
			success:function(date){
				alert(data);
			}
		})
	}
</script>
</head>
<body>
	用户名：<input type="text" id="uesrname" onblur="a()">
</body>
</html>